Ejection Fraction | MedStar Health

Ejection fraction test is the measurement of the percentage of blood leaving the heart when it contracts or squeezes. When the heart relaxes after contraction, the two lower chambers (ventricles), fill with blood. The ejection fraction (EF) is normally measured in the left ventricle, the heart’s main pumping chamber, and is recorded as a percentage of blood leaving this chamber.

According to the American Heart Association, the classifications of ejection fraction are:

  • Normal - 50-70% left ventricle (LV) ejection fraction.
  • Mildly reduced – 41-49% left ventricle (LV) ejection fraction.
  • Reduced – 40% or less left ventricle (LV) ejection fraction.

There are various causes for a reduced ejection fraction which include:

  • Cardiomyopathy – weakness of the heart muscle
  • Heart attack that damages the heart muscles
  • Heart valve disease
  • Long term hypertension (high blood pressure)
Show Next 8 of Show All